BIOGENESIS AND AVAILABILITY OF RESOURCES IN PLANT OILS

Abstract

The economic value of oilseeds is mainly determined by the amount and kind of the triglyceride esters of long chain fatty acids, which are accumulated abundantly in the cytoplasm of the storage tissues within the seed. These so-called neutral fats serve as an energy reserve as well as a substrate for the initial syntheses in the developing seedling. The molecular specificity of the storage substance required for such functions is generally low. During evolution in certain botanical species storage oils have undergone diverse modifications, which make some of them specially desirable as fat chemical raw materials. During the recent years the contributions of plant breeding have greatly increased to make these resources economically accessible. Very good progress was obtained by plant breeders particularly in tailoring the quality, i.e., fatty acid composition of a seed oil towards specific demands of the consumers. In some cases, i.e., in changing the polyenoic fatty acid content of rapeseed oil by mutation, a limit appeared to be set to genetic selection by parameters of metabolic efficiency. More detailed genetical and physiological investigations revealed that the complex system of plant fat synthesis still offers great possibilities for genetic improvements with the conventional methods of plant breeding as well as with modern biotechnics.